Genome-wide identification and characterization of the WRKY gene family in potato (Solanum tuberosum)

WRKY proteins are a large family of plant transcription factors, which play an important role in many biological processes such as plant development, metabolism, and responses to biotic and abiotic stresses. This study aimed to develop a complete overview of the WRKY family by using the potato genome. Based on the genome-wide analysis, a total of 82 StWRKY proteins were characterized and classified into three groups (I, II, and III) and five subgroups (IIa, IIb, IIc, IId, and IIe) according to the sequence similarity, motif varieties, and their phylogenetic relationships. By using multiple sequence alignment, a novel motif, WRKYGQR, was identified from StWRKY076 along with three variations of the WRKYGQK heptapeptide (WRICYGMK, WHKCGQK, and WRICYGICK) that might execute new biological functions. Chromosomal location analysis showed that the 82 StWRKY proteins were located in 11 of the 12 chromosomes, excluding chromosome 11. Phylogenetic analyses also showed that the 82 StWRKY proteins could be clustered into three large groups and five subgroups which shared typical characters of WRKY. The results provide fundamental information to inform further analysis and understanding of WRKY gene functions in potato. (C) 2017 Elsevier Ltd. All rights reserved.